EXHIBIT 38


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                               RULES CONSTITUTING
                         THE OXFORD GLYCOSYSTEMS LIMITED
                            1989 SHARE OPTION SCHEME

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                      [Version 4 as amended in August 1995]

                                Baker & McKenzie
                              100 New Bridge Street
                                 London EC4V 6JA

                               Tel: 0171 919 1000
                               Fax: 0171 919 1999



                                      INDEX

CLAUSE                                                                      PAGE
- ------                                                                      ----

1. Definitions ............................................................    1

2. Invitation to Apply for Options ........................................    3

3. Applications for Options ...............................................    4

4. Grant of Options .......................................................    4

5. Limitations on Grants ..................................................    4

6. Exercise of Options ....................................................    5

7. Takeovers and Liquidations .............................................    8

8. Variation of Share Capital .............................................   10

9. Manner of Exercise of Options ..........................................   10

10. Administration and Amendment ..........................................   10



                     RULES OF THE OXFORD GLYCOSYSTEMS GROUP
                               SHARE OPTION SCHEME

1.          Definitions

In these Rules, unless the subject or context otherwise requires:

1.1.        "acting in concert"         shall be defined in accordance with the
                                        City Code on Takeovers and Mergers;

1.2.        "Adoption Date"             means the date on which the Scheme is
                                        adopted by the Company at a general
                                        meeting of the Company;

1.3.        "Associated Company"        has the same meaning as in Section 416
                                        of the Income and Corporation Taxes Act
                                        1988;

1.4.        "Auditors"                  means the auditors for the time being of
                                        the Company (acting as experts and not
                                        as arbitrators);

1.5.        "Board"                     means the board of directors of the
                                        Company;

1.6.        "Company"                   means Oxford GlycoSystems Limited;

1.7.        "Control"                   has the same meaning as in Section 840
                                        of the Income and Corporation Taxes Act
                                        1988;

1.8.        "Date of Grant"             means (i) the date on which an Option
                                        is, was or is to be granted under the
                                        Scheme or


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                                        (ii) at the discretion of the Board,
                                        such earlier date when the individual to
                                        whom the grant is made first became an
                                        Eligible Person as defined in Clause 1.9
                                        below;

1.9.        "Eligible Person"           means any employee or director of the
                                        Company or any Associated Company or any
                                        individual who provides consultancy
                                        services to the Company or any
                                        Associated Company;

1.10.       "OGSG"                      Oxford GlycoSystems Group PLC;

1.11.       "Option"                    means a right to subscribe for Shares
                                        granted (or to be granted) in accordance
                                        with these Rules and including (unless
                                        the context requires otherwise) a
                                        Replacement Option;

1.12.       "Replacement Option"        means a right to subscribe for Shares
                                        granted in accordance with these Rules
                                        over an equivalent number of Shares to
                                        those subject to an Option which has
                                        lapsed on the seventh anniversary of its
                                        Date of Grant pursuant to Rule 6.4.1;

1.13.       "Scheme"                    means an ordinary share option scheme
                                        constituted and governed by these Rules
                                        as from time to time amended;

1.14.       "Share"                     means an ordinary share in the capital
                                        of the Company;


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1.15.       "Subscription Price"        means the price at which each Share
                                        subject to an Option may be acquired on
                                        the exercise of that Option being the
                                        amount specified by the Board in its
                                        sole discretion;

1.16.       "Subsisting Option"         means an Option which has neither lapsed
                                        nor been exercised.

2.          Invitation to Apply for Options

At any time after the Adoption Date, the Board may in its absolute discretion
select any number of individuals who shall be, or were at the intended Date of
Grant, Eligible Persons and invite them to apply for the grant of Options to
acquire Shares in the Company. Each invitation shall specify:

2.1.        the date (being not later than 14 days after the issue of the
            invitation) by which an application must be made;

2.2.        the maximum number of Shares over which that individual may on that
            occasion apply for an Option, being determined at the absolute
            discretion of the Board save that it shall not be so large that the
            grant of an Option over that number of Shares would cause the limit
            specified in Rule 5 to be exceeded;

2.3.        the Subscription Price at which Shares may be acquired on the
            exercise of any Option granted in response to the application; and

2.4.        in the case of Replacement Options, the time or times at which the
            Replacement Option is to become exercisable.

Each invitation shall be accompanied by an application in such form, not
inconsistent with these Rules, as the Board may determine.


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3.          Applications for Options

Not later than the date specified in the invitation each Eligible Person to whom
an invitation has been issued in accordance with Rule 2 above may apply to the
Board, using the application form supplied, for an Option over a number of
Shares not exceeding the number specified in the invitation.

4.          Grant of Options

Not later than the twenty-first day following the issue of invitations the Board
may grant to each applicant who is still an Eligible Person an Option over the
number of Shares specified in his application provided that, where the granting
of Options to meet all the applications received would result in the limit
specified in Rule 5.1 being exceeded, the Board shall scale down the
applications or select among the applicants as it sees fit to ensure that the
aforesaid limit will not be exceeded.

As soon as possible after Options have been granted the Board shall issue a
certificate of Option in respect of each Option in such form, not inconsistent
with these Rules, as the board may determine. Each Option shall be granted under
the Common Seal of the Company.

No Option may be transferred, assigned or charged and any purported transfer,
assignment or charge shall cause the Option to lapse forthwith. Each option
certificate shall carry a statement to this effect.

5.          Limitations on Grants

5.1.        No Option shall be granted pursuant to Rule 4 above if such grant
            would result in the aggregate of:

5.1.1.            the number of Shares over which Subsisting Options have been
                  granted under this Scheme;


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5.1.2.            the number of Shares which have been issued on the exercise of
                  Options granted under this Scheme;

            exceeding the greater of (i) 1,900,000 Shares or (ii) 10% of the
            Shares then in issue.

For the purposes of this Rule 5 Options shall include all Options granted under
this Scheme and all options granted under any other scheme established by the
Company or any Associated Company thereof.

6.          Exercise of Options

6.1.        Subject to Rules 7 and 9 and Rule 6.2 below any Option which has not
            lapsed, other than a Replacement Option, may be exercised in whole
            or in part at any time following the earliest of the following
            events:

6.1.1.            as to 20% of the Shares over which the Option was granted, the
                  first anniversary of the Date of Grant;

6.1.2.            as to a further 20% of the Shares over which the Option was
                  granted, the second anniversary of the Date of Grant;

6.1.3.            as to a further 20% of the Shares over which the Option was
                  granted, the third anniversary of the Date of Grant;

6.1.4.            as to a further 20% of the Shares over which the Option was
                  granted, the fourth anniversary of the Date of Grant;

6.1.5.            as to the final 20% of the Shares over which the Option was
                  granted, the fifth anniversary of the Date of Grant,

            provided that no Option shall become exercisable in respect of a
            further percentage of Shares after (i) either the Option holder or
            the Company gives


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            notice to the other to terminate the Option holder's employment or
            directorship with the Company or any Associated Company or (ii) the
            Company passes a resolution for a voluntary winding-up.

6.2.        Subject to Rules 7 and 9 below, the Board may stipulate when
            granting any Option (other than a Replacement Option) to an
            individual who provides consultancy services to the Company or any
            Associated Company that any Option which has not lapsed may be
            exercised in whole or in part at any time following the earliest of
            the following events:

6.2.1.            as to one third of the Shares over which the Option was
                  granted, the first anniversary of the Date of Grant;

6.2.2.            as to a further third of the Shares over which the Option was
                  granted, the second anniversary of the Date of Grant;

6.2.3.            as to the remaining third of the Shares over which the Option
                  was granted, the third anniversary of the Date of Grant,

            provided that no Option shall become exercisable in respect of a
            further percentage of Shares after (i) either the Option holder or
            the Company gives notice to the other to terminate the Option
            holder's consultancy service to the Company or any Associated
            Company or (ii) the Company passes a resolution for a voluntary
            winding-up.

6.3.        Subject to Rules 7 and 9 below, any Replacement Option which has not
            lapsed may be exercised in whole or in part at any time or times
            specified by the Board pursuant to Rule 2.4 above.

6.4.        An Option shall lapse on the earliest of the following events:

6.4.1.            the seventh anniversary of the Date of Grant;


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6.4.2.            the Option holder's death;

6.4.3.            six months after the date when the Option holder ceases to be
                  a director, employee, or consultant of the Company or any
                  Associated Company by reason of

         6.4.3.1.       injury or disability evidenced to the satisfaction of
                        the Board); or

         6.4.3.2.       redundancy (within the meaning of the Employment
                        Protection (Consolidation) Act 1978; or

         6.4.3.3.       retirement at contractual retirement age or early
                        retirement by agreement with the Company or any
                        Associated Company; or

         6.4.3.4.       the transfer of the undertaking or part-undertaking in
                        which the Option holder is employed, or to which the
                        Option holder provides services, to a person other than
                        the Company or any Associated Company

         6.4.3.5.       the Company for which, or to which, the Option holder
                        provides services ceasing to be an Associated Company of
                        the Company

                  and is no longer continuing as a director, employee or
                  consultant (provided that the above-mentioned six month period
                  shall be a period of twenty four months if, at the date in
                  question, the shares of OGSG are not tradeable on any public
                  stock exchange (including for this purpose the exchange known
                  as NASDAQ);

6.4.4.            the date when the Option holder ceases to be a director,
                  employee or consultant of the Company or any Associated
                  Company for any reason other than one of the reasons referred
                  to in Rule 6.4.3 above and is


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                  no longer continuing as a director, employee or consultant of
                  the Company or an Associated Company;

6.4.5.            six months after the Option has become exercisable in
                  accordance with Rules 7.1 or 7.2 or, in the case of Rule 7.3,
                  the date when any person ceases to be bound or entitled as
                  mentioned therein; and

6.4.6.            the Option holder being adjudicated bankrupt.

7.          Takeovers and Liquidations

7.1.        If any person:

7.1.1.            obtains Control of the Company; or

7.1.2.            obtains control of OGSG as a result of making:

7.1.2.1.          a general offer to acquire the whole of the issued ordinary
                  share capital of OGSG which is made on a condition such that
                  if it is satisfied the person making the offer will have
                  Control of OGSG; or

7.1.2.2.          a general offer to acquire all the shares in OGSG which are of
                  the same class as the shares;

            then any Subsisting Option may be exercised in full (regardless of
            the extent to which it had by then become exercisable under Rules
            6.1.1. to 6.1.5. or 6.2.1. to 6.2.3. above or, in the case of
            Replacement Options, under the terms relating to the time or times
            of exercise originally imposed by the Board pursuant to Rule 2.4
            above) within six months of the time when the person making the
            offer has obtained Control of the Company or OGSG as the case may be
            and any condition subject to which the offer is made has been
            satisfied. Provided that in the event of Rule 7.3 applying in
            relation to the same change of Control, the right to exercise a
            Subsisting Option under this


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            Rule 7.1 shall terminate upon the person referred to in Rule 7.3
            below ceasing to be bound or entitled as referred to in Rule 7.3.

7.2.        If the Company passes a resolution for voluntary winding up, any
            Subsisting Option may be exercised within six months of the passing
            of the resolution.

7.3.        If any person becomes bound or entitled to acquire shares in the
            Company or OGSG under sections 428 to 430 of the Companies 1985,
            then any Subsisting Option may be exercised in full (regardless of
            the extent to which it had by then become exercisable under Rules
            6.1.1 to 6.1.5 or 6.2.1 to 6.2.3 above or, in the case of
            Replacement Options, under the terms relating to the time or times
            of exercise originally imposed by the Board pursuant to Rule 2.4
            above) at any time when that person remains so bound or entitled.

7.4.        For the purposes of this Rule 7, a person shall be deemed to have
            obtained Control of the Company or OGSG as the case may be if he and
            others acting in concert with him have together obtained Control of
            it, provided however that no change of Control shall be deemed to
            occur by reason of changes in the percentage of ownership of the
            shareholders as of the date immediately following completion of the
            transactions contemplated in the Investment Agreement dated 14
            September 1988 between the Company, Advent Euroventures Limited
            Partnership and others, and provided further that no change of
            Control shall be deemed to occur by reason of the acceptance by
            shareholders of the offers made in a circular dated 19 November 1992
            by OGSG to acquire all the Shares of each class in the capital of
            the Company in exchange for new Shares in OGSG.

7.5.        The exercise of an Option pursuant to the preceding provisions of
            this Rule 7 shall be subject to the provisions of Rule 9 below.


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8.          Variation of Share Capital

In the event of any capitalization or rights issue or any consolidation,
sub-division or reduction of capital by the Company or OGSG, the number of
Shares subject to any Option and the Subscription Price for each of those Shares
shall be adjusted in such manner as the Auditors confirm in writing to be fair
and reasonable provided that the aggregate amount payable on the exercise of an
Option in full is not increased.

9.          Manner of Exercise of Options

9.1.        No Option may be exercised at any time when the shares which may be
            thereby acquired are not Shares as defined in Rule 1.

9.2.        An Option shall be exercised by the Option holder, or as the case
            may be his personal representatives, giving notice to the Company in
            writing of the number of Shares in respect of which he wishes to
            exercise the Option accompanied by the appropriate payment and the
            relevant option certificate and shall be effective on the date of
            its receipt by the Company.

9.3.        Shares shall be allotted and issued pursuant to a notice of exercise
            within 30 days of the date of exercise. Save for any rights
            determined by reference to a date preceding the date of allotment,
            such Shares shall rank pari passu with the other shares of the same
            class in issue at the date of allotment.

10.         Administration and Amendment

10.1.       The Scheme shall be administered by the Board whose decision on all
            disputes shall be final.

10.2.       The Board shall be entitled at any time to appoint a committee to be
            known as the "Compensation Committee", and to consist of such
            persons as the Board shall in its sole discretion determine. The
            Compensation Committee will be entitled to exercise all powers given
            to the Board by these Rules, including but


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            not limited to the power to issue invitations to apply for the grant
            of Options pursuant to Rule 2, but excluding the power to amend
            these Rules pursuant to Rule 11.3 below. The procedure to be
            followed by the Compensation Committee in exercising such powers
            shall be determined by the Board, which will also be entitled to
            suspend or disband the Committee at any time.

10.3.       Any notice or other communication under or in connection with the
            Scheme may be given by the Company either personally or by post and
            to the Company either personally or by post to the secretary; items
            sent by post shall be pre-paid and shall be deemed to have been
            received 72 hours after posting.

10.4.       The Company shall at all times keep available sufficient authorised
            and unissued Shares to satisfy the exercise to the full extent still
            possible of all Options which have neither lapsed nor been fully
            exercised, taking account of any other obligations of the Company to
            issue unissued Shares.


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                           OXFORD GLYCOSYSTEMS LIMITED
                            1989 SHARE OPTION SCHEME

                               INVITATION LFTTER

To:         [the employee]                                                  Date

1.          You are hereby invited to apply for an option over up to Ordinary
            Shares of one penny each of Oxford Glycosystems Limited at a price
            of ________ per share, under the terms of the Scheme. This
            invitation may be accepted only by completing the enclosed
            Application Form and sending it to the company to be received by not
            later than [                    ].

To be inserted in respect of Replacement Options:

[2.         Your option will be exercisable as follows: [insert time (or times)
            when the option will be exercisable and the extent to which it will
            be exercisable at those time(s)].]

Yours faithfully


OXFORD GLYCOSYSTEMS LIMITED


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                           OXFORD GLYCOSYSTEMS LIMITED
                            1989 SHARE OPTION SCHEME

                                APPLICATION FORM

To:         Oxford Glycosystems Limited ("the Company")

Date:

I have received a letter inviting me to apply for an option over not more than
[ ] Ordinary Shares of one penny each of the Company at a price of [           ]
per Share under the terms of the Share Option Scheme.

I hereby apply for the grant of an option to subscribe for [           ] Shares.
I note that, if my application for the grant of an option over the Shares is
granted in part or in full, any option to subscribe for or purchase Shares will
be upon and subject to all the terms, conditions and provisions of the Share
Option Scheme. I hereby agree to be bound in contract with the Company to
observe the Rules of the Share Option Scheme (a copy of which I have received)
and any conditions notified to me by the Company.

Yours faithfully


[the Employee]


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OPTION CERTIFICATE NUMBER

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                          OXFORD GLYCOSYSTEMS LIMITED

                   (Registered in England under No. 2271935)

TOTAL NUMBER OF ORDINARY SHARES INCLUDED IN THIS OPTION

This is to certify that _________________ was granted an Option on the _____ day
of _________ to subscribe for _______ shares of ________ each in Oxford
Glycosystems Limited at a Subscription Price of _____ per share upon the terms
of the Oxford Glycosystems Limited 1989 Share Option Scheme. The Option, which
may not be assigned or transferred, may be exercised at the time and in the
circumstances [permitted in the Scheme]. [In the case of Replacement Options:
specified in your Invitation Letter.]

                                                   Signed on behalf of
                                                   Oxford Glycosystems Limited


Date __________________         ____________________   Director

Notes:

(1)   This certificate must be surrendered on the exercise in whole or in part
      of the Option.

(2)   The number of shares covered by this Option and/or the Subscription Price
      may be varied in accordance with the Rules of the Scheme.


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                           OXFORD GLYCOSYSTEMS LIMITED
                            1989 SHARE OPTION SCHEME
                          NOTICE OF EXERCISE OF OPTION

To:         Oxford Glycosystems Limited ("the Company")

Date:

I hereby exercise my option to subscribe for [                   ] Ordinary
Shares of one penny each in the Company at a price of [    ] per share.

I attach my original option certificate number [              ] for notation of
the number of Ordinary Shares over which I have exercised this Option.

I enclose my cheque for (Pound)         [being the number of shares referred to
above multiplied by the price per share].

I request you to allot to me the shares referred to above, subject to your
Memorandum and Articles of Association and to the Rules of the Company's 1989
Share Option Scheme and to despatch a share certificate to me.


Yours faithfully

Notes:

(1)   This notice will not be valid unless it is accompanied by the original
      option certificate, and a cheque for the total amount payable on exercise.


(2)   The notice may refer to all or just some of the shares covered by the
      option certificate. If it refers to only some of the shares, the option
      certificate will be noted and returned to me.


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(3)   The times at which, and the conditions subject to which, an option may be
      exercised are [set out in the Rules of the Scheme]. [In the case of
      Replacement Options: set out in the Rules of the Scheme and in your
      Invitation Letter].


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